public class ClimbStairs {
    // 爬楼梯
    // https://leetcode.cn/problems/climbing-stairs/?envType=study-plan-v2&envId=top-100-liked
    public int climbStairs(int n) {
        int[] dp = new int[n+1];
        dp[0] = dp[1] = 1;
        for (int i = 2; i <= n; i++) {
            dp[i] = dp[i-1] + dp[i-2];
        }
        return dp[n];
    }
}
